CVE-2026-73905 in Helidon
Summary
by MITRE • 08/19/2026
Vulnerability in the Helidon product of Oracle Fusion Middleware (component: Imperative Web Server). The supported version that is affected is 4.5.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Helidon. Successful attacks of this vulnerability can result in takeover of Helidon. CVSS 3.1 Base Score 9.8 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).
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Analysis
by VulDB Data Team • 08/19/2026
The identified vulnerability resides within the Imperative Web Server component of Oracle Fusion Middleware Helidon, specifically affecting version 4.5.0. This critical security flaw permits an unauthenticated attacker to achieve complete system compromise through network access via HTTP. The severity is quantified by a CVSS v3.1 base score of 9.8, indicating high risk across all three core pillars of information security: confidentiality, integrity, and availability. The vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) confirms that the attack requires no prior authentication, involves low complexity, does not require user interaction, and results in significant impacts on all security attributes for an unmodified system environment.
From a technical perspective, this vulnerability likely stems from insufficient input validation or improper handling of HTTP requests within the imperative web server implementation. Such flaws typically allow attackers to inject malicious payloads that exploit logic errors or buffer overflows, leading to arbitrary code execution or denial of service conditions. The absence of authentication requirements means that any entity with network connectivity to the affected Helidon instance can attempt exploitation without needing valid credentials. This characteristic significantly lowers the barrier for entry, enabling both automated scanning tools and targeted attackers to compromise the system remotely.
The operational impact of a successful exploit is severe, resulting in full takeover of the Helidon service. An attacker gaining control over this component can manipulate application logic, exfiltrate sensitive data stored or processed by the middleware, alter configurations, or disrupt services entirely. Given that Helidon serves as a foundational web server for many enterprise applications built on Oracle Fusion Middleware, compromising it may provide lateral movement opportunities within the broader network infrastructure. The high availability impact suggests that denial of service is also a viable outcome, potentially causing significant downtime and business disruption for organizations relying on this middleware stack.
This vulnerability aligns with CWE-20 Improper Input Validation and CWE-78 OS Command Injection if command execution is involved, or CWE-94 Code Injection depending on the specific mechanism exploited. In terms of MITRE ATT&CK mapping, the attack vector corresponds to Initial Access via Network Service Exploitation (T1190) and potentially Privilege Escalation (T1068) if local privileges are gained post-exploitation. The lack of authentication requirement places it firmly within remote exploitation categories that require immediate attention due to their ease of use by threat actors.
Mitigation strategies must prioritize immediate patching or upgrading Helidon to a version where this vulnerability has been remediated, as Oracle typically releases security patches for such critical issues in subsequent updates. In the interim, network-level controls should be implemented to restrict access to the affected HTTP ports only from trusted IP addresses using firewalls or access control lists. Additionally, deploying Web Application Firewalls with rulesets designed to detect and block common injection patterns can provide a layer of defense against exploitation attempts. Monitoring logs for unusual HTTP request patterns indicative of automated scanning or exploit scripts is also recommended to identify potential attack activity early. Organizations should conduct thorough vulnerability assessments across their middleware infrastructure to ensure no other instances remain exposed until the patch is applied.